ALGIERS: Thousands of Algerian protesters rejected the interim leader named Tuesday to replace former President Abdelaziz Bouteflika, shouting “out with the system” as they demonstrated for the dismantling of the political hierarchy that has led Algeria for two decades. The North African country’s influential military stayed silent on the appointment, saying only that it would work to ensure the “tranquility” of the country.

A student protest had been timed to coincide with the Algerian Parliament’s decision to designate the upper chamber’s leader, Bouteflika ally Abdelkader Bensalah, as interim president.

Within an hour of the announcement, police moved in on the demonstrators, dousing them with pepper spray, shooting bursts from a water cannon and using batons to break up the crowd of thousands on a central avenue. The tensions, which continued into the afternoon, were unusual for the Algerian pro-democracy movement.

Weeks of overwhelmingly peaceful protests forced Bouteflika to step down last week after 20 years in office. That is giving new hope to millions of young Algerians frustrated by corruption, unemployment and repression - even as it has raised concerns about what’s next for the energy-rich country that’s a key partner in the international fight against terrorism.

“All in all, the way in which the vacancy of the presidency of the Republic has been filled does not bring our country closer to the end of the crisis,” said Ali Benflis, leader of the opposition Talae El Houriyet party.

As called for by the Algerian Constitution, Bensalah was appointed to an interim post for a maximum of 90 days until a new election can be organized. He can’t run for president himself when the election is held. Members of the opposition abstained from Tuesday’s vote.

“I am required by national duty to take on this heavy responsibility of steering a transition that will allow the Algerian people to exercise its sovereignty,” Bensalah said.

The Defense Ministry said in a statement Tuesday that the army would work to ensure “the Algerian people’s legitimate right to enjoy total tranquility for the present and the future.”

The much-awaited but inconclusive statement suggests the army will wait to see if there are new mass protests Friday before deciding whether to throw its support behind Bensalah or not.

The statement didn’t specifically address Bensalah’s appointment.

Algeria’s powerful army chief Gen. Ahmed Gaid Salah turned against Bouteflika last week and sided with the protesters, leading to the president’s departure. However many protesters have shown frustration with the army, too.

With Bouteflika out, protesters are mainly focusing their anger on other key figures, dubbed the “three Bs”: Bensalah, Prime Minister Noureddine Bedoui and the head of the Constitutional Council Tayeb Belaiz.

“Appointing Bensalah will fuel anger and it could radicalize the protesters,” taxi driver Hassen Rahmine said.

“Out with Bensalah, Belaiz and Bedoui!” protesters shouted at Tuesday’s rally in Algiers that converged at the plaza in front of the main post office, a symbol of the country’s pro-democracy movement.

Bensalah, 77, has cultivated a low-key profile despite holding numerous positions over the past quarter-century. With a career as a devoted public servant, he has no political weight, and his powers as transitional leader are reduced.

Bedoui has a starkly different profile. He was among the early promoters of a fifth mandate for the ailing Bouteflika - the trigger for the crisis. Mohamed Saidj, a political science professor, said that as interior minister, Bedoui also was behind forbidding doctors and human rights organizations from protesting. As for Belaiz, “everyone knows that he is Bouteflika’s man,” Saidj said in a recent interview.